Humidification of synthetic sausage casings

ABSTRACT

Method and apparatus for shirring synthetic sausage casings, e.g. regenerated cellulose, amylose, alginate, collagen casings, etc., wherein a flattened tubular casing is fed from a storage reel, inflated, and shirred mechanically and the casing, after leaving the storage reel and prior to being discharged from the shirring apparatus, is passed axially through a symmetrical, radially converging pattern of water in which the casing is contacted by and consequently adsorbs a predetermined metered amount of water. The spraying of the casing preferably is effected by an annular spray nozzle having a plurality of equiangularly spaced orifices positioned in its inner periphery to direct water uniformly onto the outside surface of the casing. Control of the spraying is accomplished by positioning valve control means in the water feed line to the spray device and operatively connecting the valve means to be responsive to the operation of the means for feeding casing through the shirring machine.

United States Patent Martinek [151 3,657,769 1 Apr. 25, 1972HUMIDIFICATION 0F SYNTHETIC SAUSAGE CASINGS Inventor! Thomas W.Martlnelt, Covington, Ind.

Tee-Pelt, Inc., Chicago, Ill.

Dec. 29, i969 Assignee:

Filed;

App]. No.:

US. CI.

in. CI. A22c 13/00 mu oISeur-eh ..17/42, 49; 239/567 [56] ReferencesCited UNITED STATES PATENTS l0/l945 Klingen..,.. ..239/567 X [2/ l 9656/1967 8/ I969 9/ l 969 FOREIGN PATENTS OR APPLICATIONS 459,793 9/1968Switzerland 1 7/42 Coleman et al. ..239/567 X Primary Examiner-LucieI-l. Laudenslager Attorney-Neal J. Mosely and David V. Munnis [57]ABSTRACT Method and apparatus for shirring synthetic sausage casings, I

e.g. regenerated cellulose, amylose, alginate, collagen casings,

etc., wherein a'flattened tubular casing is fed from a storage reel,inflated, and shirred mechanically and the casing, after leaving thestorage'reel and prior to being discharged from the I shirringapparatus, is passed axially through a symmetrical,

radially converging pattern of water in which the casing is contacted byand consequently adsorbs a predetermined metered amount of water. Thespraying of the casing preferably is effected by an annular spray nozzlehaving a plurality of equiangularly spaced orifices positioned in itsinner periphery to directwater uniformly onto the outside surface of thecasing. Control of the sprayingis accomplished by positioning valvecontrol means in the water feed line to the spray device and operativelyconnecting the valve means to be responsive to the operation of themeans for feeding casing through the shirring machine.

6 Claims, 4 Drawing Figures Patented April 25; 1972 i 2 Sheets-Sheet 1THOMAS w MARTINEK INVENTOR.

his attorney Patented A ril 25, 1972 2 Sheets-Sheet 3 THOMAS W MARTINEKINVENTOR.

HUMIDIFICATION OF SYNTHETIC SAUSAGE CASINGS BACKGROUND OF THEINVENTION 1. Field of the Invention This invention relates to new anduseful improvements in the shining of artificial sausage casings andmore particularly to the humidifrcation of artificial sausage casingsduring the shirring thereof.

2. Description of the Prior Art Artificial sausage casings, particularlycasings formed of regenerated cellulose, are prepared as hollow,thin-walled tubes of very great length. For convenience in handling,these casings are shirred from lengths ranging from 40-160 ft. or moredown to a shirred and compressed length of the order of a few inches. Anearly type shirring machine and the resulting shirred product are shownin Dietrich, U.S. Pat. No. 2,010,626. Improved forms of shirringmachines and the products thereof are shown in' Korsgaard, U.S. Pat. No.2,583,654; Blizzard et al., U.S. Pat. Nos. 2,722,714,

2,722,715, and 2,723,201; Gimbel, U.S. Pat. No. 2,819,488;

Matecki, U.S. Pat. Nos. 2,983,949 and 2,984,574; Clement,- U.S. Pat. No.3,266,81 1; Arnold, U.S. Pat. No. 3,454,982; and Martinek, U.S. Pat.Nos. 3,454,981 and 3,456,286.

In the preparation and use of artificial sausage casings, particularlycasings formed from regenerated cellulose, the moisture content of thecasings has been of extreme importance. When the casings are firstformed, it has been necessary that they be dried to a relatively lowwater content, e.g. 8-10 percent. A lower water content in the casinggenerally results in damage to the casing during the shirring operationand sometimes makes shirring completely impossible. Similarly, a highwater content has resulted in damage to the casing during shirring,usually resulting from the casings sticking to the shirring mandrel.

After a casing is shined, it is packaged and shipped to a meat packinghouse where an individual shirred strand is placed on a stuffing hornand a meat emulsion extruded to fill the casing to its fully extendedlength. The stuffing of the casing usually takes place within a fewseconds with the result that the casing is extended from a shirredlength of 8-27 in. to an extended length of 40-160 ft. or moreat a rateof 2-6 ftJsec. This rapid extension of the casing during stuffingrequires the casing to be especially strong and resistant to tearing. lfeven minor holes develop in the casing, the casing may split or breakduring stuffing and waste a large quantity of meat.

In the shirring of artificial sausage casings, the pleats which areformed are sometimes interlocked and are almost always nested in aconcave manner to provide'a tightly compressedstrand of casing forshipment and, handling. The tightly compressed and sometimes interlockedpleats require a higher moisture content to pennit extension of thecasing during the stuffing operation without tearing or breaking thecasing. In general, an average moisture content of -20 percent has beenrequired, preferably about 17-18 percent. If the shirred casing has amoisture content appreciably less than about 15 percent, there is atendency toward excessive breakage during stuffing. Likewise, if thecasing has a moisture content in excess of about 20 percent, the casingis too plastic and may tend to overstufi.

It is, therefore, essential that shirred casing be humidified to arelatively narrow, critical moisture content which is very uniformthroughout the length of the casing to permit stuffing without excessivebreakage.

In the past, shirred artificial sausage casings have been packaged incartons or containers which are apertured at opposite ends to pennit thecirculation of moist air through the shirred casing strands to producethe desired moisture content in the casings.

When shirring machines of the type shown in Dietrich, U.S. Pat. No.2,010,626 were in use, the shirred casings which were produced wereaccordion pleated but did not have nested concave pleats which weretightly compacted to provide shirred strands which were self-supporting.As a result, the shirred casing strands had to be packaged in smallindividual packages which were easily removed from the strand at thepacking house after insertion over a stuffing horn. These individualcartons were apertured on both ends, and the packaged casings werehumidified by passing moist air through and over the casing strands.

At a later date, a package was developed for shirred casings, as shownin Hewitt, U.S. Pat. No. 2,181,329, which had a plurality of aperturesat opposite ends and which would contain a large number of shirredcasings. The Hewitt package was designed to permit the packaging of anumber of shirred cas ing strands while providing for circulation ofmoist air through and about the strands to bring the moisture content tothe level required for satisfactory stuffing.

An improvement on the shirred casing carton of Hewitt is described andclaimed in Firth, U.S. Pat. No. 2,794,544. The Hewitt and Firthpackages, however, are both subject to'substantial objections incommercial use. These packages are expensive to make because of thespaced perforations required in the ends of the cartons and suffer fromsevere mechanical weakness in the perforated end walls which result inbreakage of the end walls from time to time. a

The development of improved shirring machines of the type shown in theKorsgaard, Blizzard et al., Gimbel, Matecki, Clement, Arnold, andMartinek patents made possible the shirring of greater lengths of casingthan had been previously possible. The Blizzard et al. shirring machineproduced a shirred casing having accordion pleats which were nestedtightly in a concave manner with the result that the shirred andcompressed casing could be held without external support. As the casingindustry has tended to produce longer and longer shirred strands, e.g.today strands up to ft. are shirred, the problem of humidifying casingto the critical moisture content required for satisfactory stufiing hasbecome increasingly difficult. In longer lengths of shirred casing,there is a considerable resistance to flow of moist air through thecasing with the result that the ends of the casing tend to be more moistand the center of the casing less moist. Also, the moist airhumidification technique has not been entirely practical for thehumidification of heavy gauge casings and fibrous casings used forpackaging of larger sausages and chunks and pieces of meat.

A technique for the humidification, during shirring, of syntheticsausage casings to the critical moisture content required forsatisfactory stuffing is disclosed in Arnold et al.,

U.S. Pat. No. 3,222,192. In this technique, moisture is transferredexternally to 'dry casing reel stock by the metering rolls,

feed belts, shirring belts or shirring wheels. However, the use that theshirring machine is stopped, unshirred casing is between the moistenedbelts, rolls, and the like for suficient time to adsorb most of thewater on the contacting surfaces of the elements. This results in theapplication of a large excess of water to a small section of the casingduring the time that the machine is at rest. The overly wetted casingconsequently is more susceptible to damage when shirring is resumed.

Attempts to suitably humidify casing by contact with wet belts, rolls,and the like also suffer from a further disadvantage. Proper metering ofthe water is difficult since, at the rotational speeds of the belts,rolls, or wheels used to transfer the water to the casing, significantamounts of water are thrown off the rotating surfaces in directions awayfrom the casing.

Another approach involves the use of a porous capillary applicatorcontacting the casing after leaving the storage reel and prior to thepoint where the shirred product is discharged from the shirringapparatus. This method is disclosed in Martinek, US. Pat. No. 3,462,794.This improvement obviates the need for a surfactant but still suffersdrawbacks due to a nonunifonn application of water, insufficienttransfer rates, plugging of capillary passages and occasionalnon-contacts due to casing size variations or misalignments. Also, adifferent size capillary applicator is required for each different sizeof easing.

STATEMENT OF OBJECTS AND FEATURES Accordingly, it is the primary objectof this invention to provide a new sausage casing shirring apparatuswhich also provides for improved humidification of sausage casings.

Another object of this invention is to provide a new shirring apparatuswhich produces uniformly humidified shirred synthetic sausage casings.

An additional object of this invention is to provide a new sausagecasing shirring apparatus adapted to operate intermittently and produceuniformly humidified shirred sausage casrngs.

A further object of the present invention is to provide a new sausagecasing shirring apparatus adapted to controllably and uniformly humidifysausage casings of widely varying sizes to predetermined moisture levelswithout the use of wetting agents and with relatively little loss ofhumidification fluid.

Yet another object of the present invention is to provide a new andimproved method for shirring sausage casings wherein the shirred casingsproduced advantageously are uniformly humidified to predeterminedmoisture content.

Features of the present invention are the provision of a new andimproved sausage casing apparatus and method for shirring andhumidifying sausage casing having as characteristics the propertiesdescribed in the above objects. 7

SUMMARY OF THE INVENTION This invention comprises a new and improvedmethod and apparatus for moistening synthetic sausage casings during theshirring thereof. More particularly, the apparatus of this invention isprovided with conventional means for feeding casing onto a supportmandrel, inflating the casing supported on the mandrel, and shirring theinflated and supported casing, and further includes controlled means forapplying water or other fluid to the inflated casing prior to its beingshirred, which controlled fluid applicator means is adapted to deliver,in response to the operation of the casing feeding means, me-

. tered amounts of water or other fluid uniformly onto the exteriorsurface of the inflated casing in the form of a symmetrical spraypattern convergent of the axis of the inflated casing. The term "spray"as used herein is intended to refer to fine directional streams ofliquid and to embrace directed fine streams which are continuous anddirected fine streams wherein separate droplets of the liquid arepresent. The type of spray delivered depends primarily upon the size andshape of the orifice or orifices of the spray applicator and thehumidification fluid feed pressure thereto. The spray can be deliveredthrough the orifices of one or more commonly supplied spray deviceswhich are disposed about the periphery of the casing and adapted tospray water in one (i.e. a curtain) or more streams. Means are providedfor supplying metered amounts of water or other fluid to the spraydevice or devices, using a common manifold in the latter case. Thesupply means includes valve means for controlling the fluid feed to thespray device or manifolded devices, which valve means is operativelyconnected to the casing feeding means of the apparatus to be responsiveto the actuation and deactuation of the casing feeding means wherebyupon the actuation of the casing feeding means the valve means is openedand upon the deactuation of the casing feeding means the valve means isclosed.

The combined features of the shirring apparatus of the present inventionenable sausage casings to be shirred and uniformly humidified topredetermined moisture contents. Application of the humidifying liquidto the casing as a spray results in several significant advantages.Unexpectedly it was there is shown an angle iron welded frame 1 whichincludes a found that casing-humidifying amounts of water sprayed ontothe exterior of inflated casing, particularly in instances wherein thedirected water is in the form of fine continuous streams, areessentially totally adsorbed by and become uniformly distributedthroughout the casing and that there is relatively little loss orrun-off of humidification liquid delivered to the casing. In fact, incases wherein water is applied to the casing in the form of finecontinuous streams, no liquid run-off from the casing is observed at allexcept at points where an already moistened casing comes into contactwith feeding belts and the like, and then the loss observed isrelatively little, i.e. on the order of 10 percent or less. Sincespraying is controlled in the apparatus of the present invention toapplyliquid to the casing only during periods during which the casingfeeding means is actuated and casing consequently is being fed past thespraying means of the apparatus, by means of the use of the shirringapparatus of the invention, humidification suitably canbe carried outeven though the accompanying shirring is intermittent, the heretoforeencountered problems of localized underand overhumidification of thecasing are eliminated, the amount of humidification liquid applied to acasing can be more closely controlled than previously possible, andhumidified casings of improved uniformity result. Furthermore, thecontrolled spray humidification-shirring apparatus of the presentinvention is more versatile than previous shirring devices having casinghumidification provisions. Previous devices relying upon belts, wheels,and the like to transfer humidification liquid to the casing by contacttherewith, usually could be employed only with casings of the same orvery similar diameter. In contrast, the apparatus of the presentinvention, using one or more spray devices which remain removed from andout of contact themselves with the casings, advantageously are adaptedto be employed to shin and humidify widely varying casing sizes.

BRIEF. DESCRIPTION OF THE DRAWINGS FIG. 1A is a detail view of part ofthe apparatus of FIG. 1 il- I lustrating an alternate location of thefluid applicator,

FIG. 2 is a side sectional view of the preferred embodiment of theassembled fluid applicator shown in FIGS. 1 and 2, and

FIG. 3 is a section view taken along line 3-3 of FIG. 2.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring now to FIG. 1 of thedrawings, the improved method and apparatus of this invention isillustrated similarly as the apparatus of the type shown in theabove-described Clement and Martinek patents. In comparing the apparatusof FIG. 1 with the corresponding figure in the Clement and Martinelrpatents, the same reference numerals are not used for the same partsshown in the patents, but the correspondence of parts and manner ofoperation will be apparent. In FIG. 1,

bottom longitudinal angle (not shown), a top longitudinal angle 4, andan upright angle 5. The remaining portions of a suitable frame 1 aredisclosed in more detail in FIG. 1 of Clement and Martinek patents towhich reference is made for a more complete understanding of the same.

Mounted on the top supporting angle 4 is plate 7 which carries ameasuring roll 8. Measuring roll 8 is rotatably mounted between supportplates 9 which also support a rotatable squeeze roll 10. Cooperatingwith measuring roll 8 is a metering disc 1 1 that is arranged to operatea measuring limit switch 12 for stopping further operation of theshirring head when a predetermined length of casing has been shirred. Atear limit switch (not shown) may also be provided for stopping furtheroperation of the shirring head in the event that the casing becomestorn. Such switches are described in detail in US. Pat. Nos. 2,722,714;2,722,715 and 2,723,201. Where provided, such a tear limit switch may beoperated by a roller 13 which engages the upper side of the inflatedcasing.

Mounted on the angle iron frame 1 are shirring head support plates 14which constitute the framework for the shirring head, further details ofwhich will be described hereinafter. Mounted on plates 14 is a shirringhead motor 15 that is suitably controlled for starting, driving, andstopping the shirring head which is generally referred to as 16.

Shirring head 16 is arranged to receive a relatively thinwalledsynthetic sausage casing 17 from reel 18 that is rotatably mounted onshaft 19. As the casing 17 comes from reel 18, it is flat, and sometimesreferred to as reel stock. The casing passes between measuring roll 8and squeeze roll and then is inflated as shown'at 20. Squeeze roll 10 ismoved into and out of position by handle 21. Immediately below roller 13which operates the tear limit switch and on the under side of inflatedcasing 20 is a roller 22 carried by arm 23. Roller 22 is employed tolimit the downward movement of roller 13 when the casing is deflated.The casing is drawn over a mandrel 50 which has a central longitudinalaperture 91 through which air flows under a slight pressure to inflatethe casing to its full diameter prior to the shirring operation. Thecentral aperture also can be used, if desired, to introduce materialssuch as lubricants and coating materials into the interior of thecasing.

The inflated casing 20 is directed into shirring head 16 between guiderollers 24 which are mounted on vertical supports 25 secured to andextending from arms 26 on plate 7. Using shirring head 16 constructed asherein disclosed and with appropriate changes in the openings and theshirring dogs or lugs, it is possible to shirr a wide range of sizes ofsynthetic sausage casings. The casings with which this invention can beemployed, for example, may range in internal diameter from aboutone-half in. to about 2 in., in thickness from 1-4 mils,

and in length from about 30-200 ft. While the reel 18 contains anindeterminant length of casing, the casing wound thereon is cut intolengths of the order of 30-200 ft. depending upon the requirements ofthe meat packer. The casing is shirred to the desired length, severed,and the shirred casing removed from the machine. While the apparatus isused primarily in the shirring of cellulosic casing, it may be used inthe shirring of fibrous casing, amylose or starch film casing, collagenfilm casing, alginate film casing, etc. The shirring head shown in thisfigure can be used in conjunction with a turret as described in US. Pat.No. 2,583,654 or a floating mandrel construction as described in U.S.Pat. No. 2,010,626 or other similar arrangements.

Shirring head 16 includes upper and lower feed belts 27 which cooperateto form a closed circular passage which assists in feeding the inflatedcasing to the shirring elements of the machine. Feeding belts 27 aresupported on pulleys or wheels 29, 30, 31, and 32. Motor is connected bya drive pulley or other suitable drive mechanism (not shown) to one ofthe wheels supporting belts 27 and is operable to drive the belts incoordination to feed the casing along mandrel 50 to shirring wheels 33.

Means preferably are provided for lubricating belts 27. A lubricantstorage tank 34 is supported by plates 35 and secured to shirring headplates 14. The tank 34 has an inlet opening 36 and bottom outlet openingconnected to tubing 37 which is in turn connected to manifold 38.Manifold 38 is connected to valves 39 and outlet tubes 40 which arearranged to supply lubricant to brushes 41 which are positioned forengagement with feeding belts 27 or shirring wheels 33.

In accordance with the present invention, the shirring apparatus of thepresent invention is provided with means for humidifying casing 20 whileit is inflated and prior to its being shirred by wheels 33. Asillustrated in FIG. 1, the casing humidification means includes at leastone spray device 42 disposed in relation to inflated casing 20 to beadapted to direct water or other fluid onto the exterior of inflatedcasing 20. In FIG. 1, spray device 42 is depicted as being positioned infront of casing feeding belts 27 along the line of travel of casing 20.

Means are provided for supplying water or other fluid to spray device42. As shown in FIG. 1, spray device 42 is connected through conduit 43to a spray device feed control valve means constituted by solenoid valve44 which in turn is connected by conduit means (conduits 45, 47, and 49)to a pump ing means 48 adapted to deliver liquid to applicator device 42from a supply of water or other liquid designated generally as 51.

In accordance with the present invention, pumping means 48 is adapted todeliver liquid to spray device 42 when applicator feed control valve 44is open. When this condition exists, humidification liquid is sprayedonto casing 20. Pumping means 48 humidification liquid to applicatordevice 42. The amount of liquid sprayed onto the casing 20 ispredetermined by metering means shown diagrammatically in the system. Inthe arrangement shown, the desired metering is achieved by a meteringvalve 46, such as that shown in Martinek, U. S. Pat. No. 3,462,794,which is adjustable to varying flow rate settings, which settings may bevaried in response to indications registered by a calibrated flow meter,or other suitable flow rate measuring device 57 (shown diagrammatically)located in the humidification liquid feed line 47.

Solenoid valve 44 is operatively connected in the apparatus to beresponsive when the casing feeding means of the apparatus is actuatedand deactuated. In the embodiment depicted, the winding 44w of solenoidvalve 44 is connected across an electrical circuit containing winding15w (shown diagrammatically) of the shirring head motor and the powersource therefor generally shown as 55. In accordance with the embodimentshown, when winding 15w is energized and casing is fed through theapparatus and shirred, winding 44w of valve 44 is energized, therebyopening valve 44 and causing casing 20 fed past spray device 42 to besubjected to a spray of humidification liquid. Shirring head motor 15 isstarted and stopped by switch 56 (shown diagrammatically). When shirringhead motor 15 is de-energized by the operation of switch 56, solenoidvalve winding 44w is de-energized causing valve 44 to close andinterrupt the spraying of casing 20. By means of this arrangement,humidification liquid is applied in predetermined metered amountsuniformly along the length of casing 20 as casing'20 is fed through thehumidification zone including spray device 42.

FIGS. 2 and 3 show the preferred embodiment of the spray device 42employed in the apparatus of this invention. The spray device is anannular ring assembly comprising a housing ring member 60 and a nozzlering member 61 fitted within the housing ring. Housing ring member 60has a generally smooth inner peripheral wall surface 70. Nozzle ringmember 61, on its outer peripheral wall surface, is provided withparallel circumferential grooves 62 and 63 which form circumferentialribs 64 and 65 adjacent the outside edges of ring member 61 andcircumferential rib 66 which is upstanding between grooves 62 and 63.Rib 66 has an outside diameter which is less than the inside diameter ofhousing ring member 60. 0- rings 67 and 68 formed of a deformablematerial are positioned in grooves 62 and 63, respectively, whereby anannular chamber 69 is defined by the inside wall 70 of housing ringmember 60, rib 66, and O-rings 67 and 68. Nozzle ring member 61 isprovided on its inside peripheral surface with a plurality of orifices72 which are equiangularly spaced apart and which communicate withannular chamber 69 through cylindrical openings 73 which radially extendthrough ring member 61. In the preferred embodiments of the invention,orifices 72 are circular openings of capillary dimensions, and morepreferably 0.004 to 0.010 in. diameter. Preferably at least four, andmore preferably at least eight, orifices 72 are provided. Housing ringmember 60 has an opening 75 having threads 76 for receiving the end of ahumidification liquid feed conduit such as conduit 43 shown in FIG. 1which thus communicates through opening 75 with annular manifold chamber69 of the spray device. The spray device assembly is held together bybolts 80 on which are located spacer elements 82,-

washers 83, and nuts 81. A support element 84 on one of plates 14 (seeFIGS. 1 and 1A) is attached to spray device 42 to support same adjacentcasing 20 in such a manner that spray device 42, mandrel 50, andconsequently inflated casing 20, are coaxial and orifices 72 of spraydevice 42 are adapted to emit a spray of water or other fluid onto theexterior surface of inflated casing 20 in a symmetrical spray patternconvergent of, and preferably normal to, the axis of casing 20. Althoughhumidification fluid ru'n-off from casing 20 is not a problem with thepresent apparatus, the inside surface of spray device 42 may be beveledas at 74 to ensure that orifices 72 remain unblocked shouldhumidification fluid application be excessive during periods of meteringalteration.

In evaluating this invention, a large number of experiments were carriedout in which difi'erent sizes, lengths and gauges of synthetic sausagecasings were shirred and humidified as heretofore described. Thisprocess has been used in the shirring of thin walled small size sausagecasings of the type used for frankfurters and other small sausages andfor heavy gauge large size cellulose casings and fibrous casings used inthe packaging of large sausages. The performance of these casings wascompared with casings which had been humidified to substantially thesame moisture content using the prior art technique of circulating moistair over shirred casing strands contained in a perforated carton. Inevaluating this humidification and shirring technique, it was necessaryto determine its effectiveness on hundreds of strands of sausage casingsto determine whether or not it would be satisfactory for commercial use.This was particularly true in the case of the thin walled small sizesausage casings. It is, therefore, impractical to set forth either byspecific example or in a tabulated form the results obtained on theapplication of this humidification and shirring technique to anystatistically significant number of shirred casing strands. A number ofregenerated cellulose casings-of the type used for production offrankfurters and other small sausages were shirred and humidified inaccordance with this invention. The casings ranged in diameter from22.50 49.50'mm. and varied in thickness from about 0.9 l.5 mils. Casingsranging from 55 160 ft. in length were shirred and humidified using theapparatus described in the several figures of the drawings. Thesecasings had an initial moisture content of about 7 9 percent and werehumidified to a moisture content of about 16 18 percent by applicationof water during shirring. Several experiments were also carried out inwhich fibrous casing having an initial water content of about 25percent. Fibrous casing was humidified and shirred in this manner andwas highly satisfactory for the preparation of large size sausages. Thefrankfurter sausage casings which were shirred and humidified in thismanner had a breakage of less than 0.5 percent which is equal to orlower than the breakage of casings of the same size which were shirreddry and then humidified to the same moisture content using the moist airhumidification of the prior art.

Especially advantageous results were obtained using a spray applicatordevice of the type shown in FIGS. 2 and 3 having eight circular orificesof a diameter of 0.006 in. 0.010 in., a length of 0.02 0.4 in., andarranged equiangularly in a circular pattern having a diameter of 1.210, more preferably 1.2 4, times outside diameter of the casing beingsprayed and with the applicator device operating at a feed pressure of 24 psig to moisten casings being fed through-the apparatus at casing feedand shirring speeds of 10 20 ft./sec. by contact with fine continuousstreams of water.

As stated, one of the principal advantages which has resulted from thisinvention is a more uniform humidification of shirred casings along theentire length and along the major and minor pleat structure. Casingswhich have been humidified to a moisture content of l7 18 percent usingthe prior art moist air humidification technique often vary as much as 3percent in moisture content between the major and minor pleats and varyeven more in moisture content along the length of the shirred casingstrand. For example, a 160 ft. shirred casing (29 in. shirred length)was humidified to an average moisture content of 18 percent using theprior art moist air humidification technique. The moisture content ofthe casing was found to vary from 20 21 percent at the extreme ends to12 percent at the center of the strand. The moisture will distributeevenly within the casing strand upon extended storage, but substantialdifferences in moisture content between the ends and middle of thestrand have been I found after storage periods of 60 90 days and longer.A I60 ft. shirred strand (20 in. shirred length) was humidified to a l718 percent moisture'content using the procedure of this invention asdescribed above, and the moisture content had no measurable variationalong the length of the casing and between the major or minor pleats orthe inside or outsideof the shirred strand.

While this invention is particularly applicable to the shirring andhumidifying of sausage casings of cellulose of the type used for thepreparation of frankfurters, the process is obviously applicable to theshirring and humidification of a wide range of casings. The process isprimarily useful for thin walled regenerated cellulose casings but canbe used for sausage casings of thicker wall construction of the typeused for processing large sausages, e.g. bolognas, etc., and may be usedfor fibrous casings or casings of a non-cellulosic type, e.g. alginate,amylose, starch, collagen, etc.

Other embodiments which do not depart from the spirit and scope of thepresent invention, of course, will be apparent to those skilled in theart. Accordingly, it will be understood the present invention is to belimited only by the scope of the appended claims.

What is claimed is:

l. A sausage casing shirring apparatus comprising 1. a mandrel on whichsausage casing is supported for shirring, said mandrel being providedwith means for inflating casing supported thereon,

2. means for shirring said casing supported and inflated on saidmandrel,

3. means for feeding a continuous length of said casing onto saidmandrel and into engagement with said shirring means,

4. means for humidifying said mandrel-supported and inflated casing to apredetermined moisture content prior to the, engagement of said casingwith said shirring means, said casing humidifying means comprising a a.a plurality of spray-emitting orifices of substantially capillarydimensions positioned equia'ngularly around and equidistant from theaxis of said casing and opera ble to spray humidification liquid in aplurality of streams onto the exterior of the inflated casing prior toshirringin a symmetrical spray pattern convergent on the axis of saidcasing, and

b. means for supplying predetermined metered amounts of humidificationliquid to said spray device, said liquid supply means including valvemeans for controlling liquid feed to said spray device, said valve meansbeing operatively connected to said casing feeding means to beresponsive to the actuation and deactuation of said casing feeding meanswhereby upon the actuation of said casing feeding means said valve meansis opened and upon the deactuation of said casing feeding means saidvalve means is closed.

2. The apparatus according to claim 1 wherein said spray device isprovided with at least four of said spaced, sprayemitting orifices.

3. The apparatus according to claim 1 wherein said spray device is anannular ring member having the plurality of equiangularly spaced,spray-emitting orifices positioned in the inner periphery of said ring.

v4. The apparatus according to claim 3 wherein said annular ring isprovided with at least four of said spaced, sprayemitting orifices.

1. A sausage casing shirring apparatus comprising
 1. a mandrel on whichsausage casing is supported for shirring, said mandrel being providedwith means for inflating casing supported thereon,
 2. means for shirringsaid casing supported and inflated on said mandrel,
 3. means for feedinga continuous length of said casing onto said mandrel and into engagementwith said shirring means,
 4. means for humidifying saidmandrel-supported and inflated casing to a predetermined moisturecontent prior to the engagement of said casing with said shirring means,said casing humidifying means comprising a. a plurality ofspray-emitting orifices of substantially capillary dimensions positionedequiangularly around and equidistant from the axis of said casing andoperable to spray humidification liquid in a plurality of streams ontothe exterior of the inflated casing prior to shirring in a symmetricalspray pattern convergent on the axis of said casing, and b. means forsupplying predetermined metered amounts of humidification liquid to saidspray device, said liquid supply means including valve means forcontrolling liquid feed to said spray device, said valve means beingoperatively connected to said casing feeding means to be responsive tothe actuation and deactuation of said casing feeding means whereby uponthe actuation of said casing feeding means said valve means is openedand upon the deactuation of said casing feeding means said valve meansis closed.
 2. means for shirring said casing supported and inflated onsaid mandrel,
 2. The apparatus according to claim 1 wherein said spraydevice is provided with at least four of said spaced, spray-emittingorifices.
 3. means for feeding a continuous length of said casing ontosaid mandrel and into engagement with said shirring means,
 3. Theapparatus according to claim 1 wherein said spray device is an annularring member having the plurality of equiangularly spaced, spray-emittingorifices positioned in the inner periphery of said ring.
 4. means forhumidifying said mandrel-supported and inflated casing to apredetermined moisture content prior to the engagement of said casingwith said shirring means, said casing humidifying means comprising a. aplurality of spray-emitting orifices of substantially capillarydimensions positioned equiangularly around and equidistant from the axisof said casing and operable to spray humidification liquid in aplurality of streams onto the exterior of the inflated casing prior toshirring in a symmetrical spray pattern convergent on the axis of saidcasing, and b. means for supplying predetermined metered amounts ofhumidification liquid to said spray device, said liquid supply meansincluding valve means for controlling liquid feed to said spray device,said valve means being operatively connected to said casing feedingmeans to be responsive to the actuation and deactuation of said casingfeeding means whereby upon the actuation of said casing feeding meanssaid valve means is opened and upon the deactuation of said casingfeeding means said valve means is closed.
 4. The apparatus according toclaim 3 wherein said annular ring is provided with at least four of saidspaced, spray-emitting orifices.
 5. The apparatus according to claim 3wherein said annular ring is provided with at least eight of saidspaced, spray-emitting orifices.
 6. The apparatus according to claim 1wherein said casing feeding means is electrically operated, said valvemeans is solenoid operated, and the solenoid of said valve means isoperatively connected to be energized when said casing feeding means isenergized.